Simplify the expression. $(-3n-4)(-5n+5)$
First distribute the ${-3n-4}$ onto the ${-5n}$ and ${5}$ $ = {-5n}({-3n-4}) + {5}({-3n-4})$ Then distribute the ${-5n}.$ $ = ({-5n} \times {-3n}) + ({-5n} \times {-4}) + {5}({-3n-4})$ $ = 15n^{2} + 20n + {5}({-3n-4})$ Then distribute the ${5}$ $ = 15n^{2} + 20n + ({5} \times {-3n}) + ({5} \times {-4})$ $ = 15n^{2} + 20n - 15n - 20$ Finally, combine the $x$ terms. $ = 15n^{2} + 5n - 20$